Industrial-grade mixing devices are generally divided into classes based upon their ability to mix fluids. Mixing is the process of reducing the size of particles or inhomogeneous species within the fluid. One metric for measuring the degree or “thoroughness” of mixing is the energy density per unit volume that a mixing device generates to disrupt the fluid particles. The classes are distinguished based on delivered energy densities. Three classes of industrial mixers have sufficient energy density to consistently produce mixtures or emulsions with particle sizes in a range from approximately 0 to approximately 50 microns.
Homogenization valve systems are typically classified as high energy devices. Fluid to be processed is pumped under high pressure through a narrow gap valve into a lower pressure environment. The pressure gradients across the valve and the resulting turbulence and cavitation act to break-up any particles in the fluid. These valve systems are most commonly used in milk homogenization and can yield average particle sizes in a range from approximately 0 to 1 micron.
In contrast, high shear mixer systems are classified as low energy devices. These systems typically utilize paddles or fluid rotors that turn at high speed in a reservoir of fluid to be processed, which, in many of the more common applications, is a food product. These systems are usually used when the acceptable average of particle sizes is greater than approximately 20 microns in the processed fluid.
Between high shear mixers and homogenization valve systems, in terms of the mixing energy density delivered to the fluid, are colloid mills, which are classified as intermediate energy devices. A colloid mill is a machine that is used to reduce the particle size of a solid in suspension in a liquid, or to reduce the droplet size of a liquid suspended in another liquid. This reduction is accomplished by applying high levels of hydraulic and mechanical shear via shear plates to the process liquid, thereby increasing the stability of suspensions and emulsions. Typically, colloid mills utilize a rotor shear plate and stator shear plate or cylinder. Many colloid mills with proper adjustment achieve average particle sizes of approximately 1 to approximately 25 microns in the processed fluid. These capabilities render colloid mills appropriate for a variety of applications including colloid and oil/water-based emulsion processing such as that required for everything from cosmetics, mayonnaise, or silicone/silver amalgam formation, to road and roofing-tar mixing.
However, colloid mills suffer from several problems, including low throughput and long cycle times. The prior art has attempted to solve these problems by making only minor variations with limited success.
Therefore, there is a need in the art to improve the process of modifying and emulsifying products including asphalt products, also known as bitumen products. Specifically, there is a need for a set of cyclonic shearing plates that modify and emulsify asphalt more efficiently than any shearing system of the prior art.